


What’s yours is Mine

by belislythindor



Category: Harry Potter - J. K. Rowling, Sherlock (TV)
Genre: Alpha/Beta/Omega Dynamics, Alpha/Omega, Established Relationship, Knotting, M/M, Omega Verse, Rimming
Language: English
Status: Completed
Published: 2014-07-20
Updated: 2014-07-20
Packaged: 2018-02-09 15:59:25
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 2,283
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/1989015
Author URL: https://archiveofourown.org/users/belislythindor/pseuds/belislythindor
Summary: <blockquote class="userstuff">
              <p>It all started out with a question.</p>
            </blockquote>





	What’s yours is Mine

**Author's Note:**

  * For [Aconissa](https://archiveofourown.org/users/Aconissa/gifts).



> Written for the AUlock exchange.  
> My first dive into writing Sherlock/John and Omega Verse

It all started out with a question during a charms homework session. John stopped writing so abruptly he almost spilled the inkwell. He wasn’t sure he had heard Sherlock correctly.  


“You know how I loathe repeating myself John”. The Ravenclaw sighed rather dramatically.  


“It’s just that, well… are you sure?”  


“I wouldn’t be asking you if I wasn’t sure. Before you ask yes I have looked extensively into this. I’ve looked at all the risks involved which surprisingly are very few”  


“May I ask why though? I’m not complaining about the current state of our relationship. I’m just genuinely curious.”  


“What having your tongue up my arse?” Sherlock asked, arching an eyebrow.

John turned redder than his house colours.  


“You aren’t opposed to the idea then, going by your response” The Ravenclaw inched closer to his mate pushing their homework aside. “Don’t deny that you have fantasised about the scenario on multiple occasions if your masturbatory habits are anything to go by,” he whispered the last part in John’s ear.

  


John’s pulse quickened, as a myriad of the many fantasies involving him and his mate flashed through his mind. Never in his wildest dreams did he consider that his Alpha might ask this of him. After much dancing around each other they had become a couple and mated their year previous, much to the relief of possibly half the school. John considered himself lucky that someone like Sherlock would want him as a mate. If one were to ask Sherlock he would say the contrary, that he was the lucky one to have John Watson for a mate.  


“John I want to see what its like. I know what it feels like to do it; now I want to know what it feels to like to have it done to me.” 

John turned to Sherlock and nodded. 

“Alright then let’s do this. As soon as you have everything ready we can do this”. John smiled and pulled Sherlock into his lap and kissed him breathlessly charms homework forgotten.

***  
John saw very little of Sherlock since their conversation, it was nearing six weeks when he received a note during breakfast one Wednesday morning.  


_It’s ready. Meet me this coming Hogsmeade weekend on the seventh floor once all the students have left. –SH  
_

The weekend could not come fast enough for John even quidditch practice wasn’t enough to completely distract him which his teammates took notice of. Although he only had to wait a few days, to John those days seemed eternal. He longed to hold his Alpha in his arms much so that he visibly vibrated with anticipation.  


John awoke on the morning of the Hogsmeade trip with much anticipation; he dressed quickly and went down to the Great Hall to eat a hurried breakfast. Once the students visiting Hogsmeade had left John made his way to the seventh floor. Sherlock was waiting for him just standing there calm as he could be while John fought the urge to tackle him and kiss him senseless.  


Sherlock must have been thinking the same thing, as soon as John was close enough he grabbed him and began to scent him. It really had been too long, John savoured the embrace and was reluctant to let go.  


“Come now John, I’ve been waiting for you”. He took John’s hand and led him down the corridor, “Now I need you to close your eyes”.  


John humoured his mate, closed his eyes and followed to where he led him. There was only one place in this castle where Sherlock would have been able to find all that he needed. John had only encountered this room just once in his fifth year. Of course Sherlock would know about the room of requirement, he wondered how long he had known about its existence but figured he would ask him later. He had been lost in thought he didn’t notice when Sherlock had let go of his hand.  


“You can open your eyes now”, Sherlock whispered in his ear.  


He did as he was told, the room John had been led into looked like it had been lifted right out a muggle hotel brochure that advertised their honeymoon suite. From the large bed with the softest looking sheets, the large glass vases of blooming red rose to the various candles lit all around the room.  


“You really are a romantic Mr. Sherlock Holmes”, John teased.  


The tips of Sherlock’s ears turned the most magnificent shade of red.  


“I really like it Sherlock, thank you. Now you better go get what we need”.  


Sherlock made his way across the room to a wardrobe. He withdrew two identical goblets from within, their contents were steaming. He made his way back to john and set the goblets on a bedside table adjacent to the bed.  


“Look Sherlock before we do this I want to make absolutely sure you want to do this”, John held his mate’s gaze firmly. “I don’t want to make you do something you don’t want. If at any point you feel uncomfortable please tell me and we will stop, this isn’t all about me okay? It’s not just about my pleasure it’s about yours too”.  


Sherlock nodded, “Alright John I understand”.  


Sherlock ran a hand through his hair until a few strands came loose. He deposited those strands on one of the goblets the contents of which bubbled and changed from its dark muddy colour to one that resembled wine. John did the same to the remaining goblet his turned the colour of milky tea.  


Sherlock handed John his goblet, “You should go prepare in the bathroom. You will find all that you need in there”.  


Goblet in hand John made his way to the adjacent bathroom, he locked the door behind him. Inside the bathroom he found a silk like bathrobe laid out just for him. He divested himself of all his clothes, letting them pool on the floor and put on the robe. He retrieved the goblet from he had set it; he closed his eyes and brought it to his lips, drinking the potion inside.  
This wasn’t the first time John had tried polyjuice potion so he wasn’t new to the sensation as his body changed. Sherlock had made him change into him once before in what Sherlock had deemed an experiment but this had happened before John considered him his mate. Once they had mated Sherlock used polyjuice on himself to turn into John. He wouldn’t have known about it if he hadn’t discovered Sherlock masturbating in John’s body one day in his very dormitory, whether it was planned or not Sherlock had yet to tell. He found the whole ordeal strangely erotic.  


Once he felt that the transformation was complete he opened his eyes and stole one quick glance in the mirror, and headed out.  
Sherlock was waiting for him; he had also gotten rid of his clothes and donned a robe similar to John’s that was tied loosely. He had to admit seeing his mate in his body was a bit odd but not unpleasant.  


“Come and join me John”, he reached his hand out to John.  


John took Sherlock’s hand and joined him and they both sat in the middle of the large bed. Although it was John’s own face looking back at him he could still somehow see Sherlock. He reached for Sherlock placing his hand on his chest, feeling his heartbeat fluttering just beneath his fingers.  
Sherlock reached inside the pocket of his bathrobe and produced a small vial. He uncapped it and drank its contents tossing it aside once he had downed it. Sherlock took John’s hand and squeezed it. Now they waited.  
John was nervous, taking each other’s appearance was one thing but for Sherlock to take a heat inducer while in John’s body was completely different. Sherlock may have taken polyjuice to take John’s form before, but never when John was in heat. The factors to consider were many so a heat inducer that was temporary was their safest choice.  


The heat inducer seemed to be taking its desired effect. John suddenly became aware of the most tantalizing scent; his newfound alpha cock seemed to take interest. A predatory growl escaped him. He gently pushed Sherlock down on the bed, he carefully removed his bathrobe.  


“On your stomach and tuck your knees under yourself, love. It will make things go a bit easier”. He told him while he removed his own robe.

Sherlock pushed up onto his arms and slid his knees up under himself; he grabbed a pillow nearby and laid his head upon it. 

John was hesitant at first as his fingers traced delicately down from the base of Sherlock’s spine and across his entrance which made him shiver involuntarily. Sherlock was already wet from the natural lubricant he was producing and more was dribbling out. John probed gently at his opening with his fingertips before leaning down to flick his tongue quickly across warm slick skin. Sherlock moaned quietly and his hips twitched as he could feel his omega cock stiffening. 

“Feel any good?” John asked, a bit hesitantly. Sherlock gave a quick nod which John took a sign to continue, as the warm tongue returned and Sherlock moaned again, a little louder this time. 

He licked again across his tight, rosy pucker and Sherlock made a noise he would classify as embarrassing. John knew what he himself liked. He pushed his tongue into Sherlock’s entrance  


“Go ahead,” Sherlock ground out and John complied. His slick tongue, warm and wet with natural lubrication, wedged its way slowly past the tight ring of muscle he pulled Sherlock’s cheeks apart even further. John began to fuck him with his tongue, slow and as deep as he could manage. He was drunk on the scent of omega in heat, his instincts clamouring to posses what was his. 

 

John’s fingers skidded across his mate’s thigh and reached around to take Sherlock’s erection in hand. John moaned against him and shoved his tongue further and further into him. John stroked Sherlock slowly, as though he wanted to make this last. He gave Sherlock’s erection one long last stroke. 

Pulling away gently, leaned up to whisper in Sherlock’s ear. “Can I?”

“Yes”  


John positioned himself pressed against Sherlock. John saw him tense slightly; he paused and placed a hand on Sherlock’s back.  


“You okay Love?” he asked softly.  


“I...just... I want to see your face when you fuck me”, Sherlock stammered. 

John smiled as he gently turned Sherlock on his back. John had often wondered what he looked like during the throws of heat now that Sherlock took form of John’s body he could see. It was a surreal experience.  
Sherlock was flushed, he was panting and he looked absolutely delectable. He pressed their bodies against each other. John crushed his lips against Sherlock in a bruising kiss that lacked grace but neither of them seemed to care as the heat took over and need escalated. Sherlock moaned into their kiss, they parted for air and John nosed around Sherlock’s neck.  


“Please...John...I need...I need” Sherlock whined out.  


“Shhhh...Love I know what you need”

 

John lined up his cock and pressed in, Sherlock spread his legs wider and brought his legs up around John’s waist to draw him closer. John sunk in to the hilt and started to thrust harshly into him. This got Sherlock begging for more of his cock.  


“Oh fuck...so...hot...so good. Mine...you’re mine” John cried out as Sherlock clenched around him.  


“Yours...yours only yours John”, Sherlock whined out. 

John’s hips twitched as he pushed himself up onto his arms and pulled out carefully before pushing back in, as deep as he could. The new angle had Sherlock gripping the sheets, his knuckles turning white.  


“Don’t stop...Oh Merlin don’t stop”, Sherlock babbled out. 

 

John could already feel his knot starting to swell, catching on Sherlock’s rim as he pulled out and thrust back in. He reached in between their bodies wrapping his fist tightly around Sherlock’s cock and stroked up and down in time with his plunges into Sherlock’s body. “Oh fuck...yes John...right there...RIGHT THERE!”  
John gave a few more thrust as he felt his knot sealing them together.  


“Oh...oh...fuck...JOHN!”  


Sherlock came with a scream; his body convulsing, his come spilling between them. John shouted as thick powerful pulses wracked his entire body as he emptied himself into Sherlock.  


Once they had caught their breath John moved them onto their side and waited for his knot to deflate. He wrapped his arms around Sherlock, “Sleep for a bit it’s going to be a while before we can move again”.  


***  


When Sherlock awoke he found himself alone in bed, he was about to call for John when he heard him emerging from the bathroom. The Polyjuice potion was still working the heat inducer seemed to have dissipated. John carried a washbasin and some towels and set about cleaning Sherlock. Once he was satisfied he set the basin aside and joined Sherlock in bed once again.  


“How long will the polyjuice last?”  


“That depends. How long have I been asleep?”  


“No more than two hours”, he turned to face Sherlock.  


“It shouldn’t be long then”.  


He had been right within minutes the polyjuice potion wore off; both Sherlock and John were back into their own selves.  
Sherlock took John’s hand wanting to do this once he was back in his own body. He looked straight into his mate’s eyes, “Thank you for this John”  


John smiled, “What’s yours is mine Sherlock”  


They kissed, sweetly and unhurried.

**Author's Note:**

> this fic has not been betaed all grammar errors are mine and mine alone. Also apologies if any Americanisms have slipped by on this fic.


End file.
